RAPID CITY, S.D. (AP) — The first U.S. Air Force training exercise in the recently expanded Powder River Training Complex was a success, South Dakota U.S. Sen. John Thune said.

Forty-one aircraft took part this week in the training at the enormous bomber training area over the Northern Plains. Bombers, fighter jets and refueling tankers practiced maneuvers in the airspace over the Dakotas, Montana and Wyoming on Wednesday and Thursday.

The expansion of the Powder River Training Complex was approved earlier this year after several years of study and public comment.

“It’s exciting to see the culmination of so many years of effort,” Thune said in a statement. “Our airmen must have the training they need to return safely after protecting our nation abroad.”

The new airspace roughly quadrupled the training airspace for the Air Force to span nearly 35,000 square miles, making it the largest over the continental U.S.

The move came over the objections of some people in the region who worry about military planes disrupting civilian flights, rural communities and ranching operations. Advocates said it will boost military training while reducing costs.

It is intended to be used by various military aircraft, including B-1 bombers from Ellsworth Air Force Base in South Dakota and B-52 bombers from Minot Air Force Base in North Dakota.